Machine for facilitating the stringing of lawn tennis and like rackets



w.. E. B. JAFFE 4 ,043

Jan. 30, 1934.

MACHINE FOR FACILITATING THE STRINGING OI LAWN TENNIS AND LIKE RACKETS 3 Sheets-Sheet I Filed May 17, 1933 INVENTOB WILL/HM 0 wnrw Sher/104p 777:

HTTOKNEY Jan. 30, 1934. w. E. B. JAFFE 1,945,043

MACHINE FOR FACILITATING THE STRINGING OF LAWN TENNIS AND LIKE RACKETS Filed May 17, 1953 3 Sheets-Sheet 2 lNl/E N 7'01? WILL/HM fawn/w Bin/low 777/7:

firm/way Jan. 30, 1934. w E 5, MPH: 1,945,043

MACHINE FOR FACILITATING-THE STRINGING OF LAWN TENNIS AND LIKE RACKE'TS Filed May 17, 1933 3 Sheets-Sheet 3 Patented Jan. 50, 1934 hurrah STATES MACHINE FOR FACILITATING THE STRING- ING OF LAWN TENNIS AND LIKE RACKETS William Edward Berthold Jaif, Chelsea, London, England Application May 17, 1933, Serial No. 671,461, and in Great Britain June 10, 1932 10 Claims.

This invention relates to machines for facilitating the stringing of lawn tennis and like rackets, namely machines by which the racket frame is held whilst the strings are being tightened, for example a machine as described in the specification of my United States Patent No. 1,863,059.

The object of the invention is to provide means, alternative to the means described in the said patent specification, for holding the racket frame whereby the machine is, within practical limits, rendered capable of holding a variety of racket frames of different shapes and sizes.

For the above purpose, a plurality of clamps located at suitable intervals around the racket frame and adjustable in the clamping plane are employed to hold the racket frame, and, accord ing to the invention, each such clamp is arranged not only to engage the two faces of the racket frame, but also is provided with an abutment located and adjustable in the plane of the clamped racket and external to and directed towards the racket frame, against the outer periphery of which it can be adjusted to abut. I

Preferably, the clamp has a pair of clamping jaws arranged equally to approach the clamping plane with a parallel motion.

By a parallel motion is meant that the jaws of the clamp do not move angularly relatively to each other.

A clamp according to the invention and the head of a machine for facilitating the stringing of rackets and having a set of clamps mounted thereon, are illustrated by way of example on the accompanying drawings, in which:-

Fig. 1 is a perpective view of the head of a machine having a plurality of the clamps in position thereon for clamping a racket, and

Fig. 2 is a plan of the machine head with the clamps removed.

On a larger scale:

Fig. 3 is a sectional side elevation of a clamp, and

Fig. 4 is an end view thereof.

a is the head of the machine on which a racket frame 22 is adapted to be held by clamps c. This head a is rotatable on a vertical pivot at relatively to a winding drum (not shown) as described in my prior patent specification No. 1,863,059.

The head a of the machine has brackets e at intervals around its periphery. The brackets 6 each have a plurality of slots f for the reception of a screw-threaded stem 57 (Figs. 3 and 4) of the respective clamp 0. whereby the clamp 0 can be adjusted in the clamping plane relatively to the head a and clamped to the respective bracket e bya winged nut h.

To hold the racket frame I) on the head a, at least one clamp c is mounted on each bracket e. Each bracket 6, however, is provided with a plurality of slots 1, so that when in the course of stringing access is required to a stringing hole in the racket frame b, obstructed by a clamp c,a substitute clamp can be mounted in one of the vacant slots f alongside such obstructing clamp, and adjusted to hold the racket frame, whereupon the obstructing clamp can be removed, without the hold on the racket frame being relaxed. The removed clamp can be eventually replaced in the same or another position.

As illustrated more particularly by Figs. 3 and 4, each clamp c has a frame 2' in the form of a two-partcasing, mounted on the above mentioned screw-threaded stem g. In this frame i are journalled two screws 7'. Each screw 7' has two screwthreaded portions of uniform but opposite pitch. A pinion k is fast on each screw 51'. The pinions R: of both screws 7 gear with an intermediate pinion Zon a spindle m located between the two screws 7' and likewise journalled in the frame 2'.

n are the two jaws of the clamp c which are mounted as nuts on and extend perpendicularly to the two screws 9', each however being mounted on portions of the screw thread of both screws of opposite pitch to that on which the other is mounted.

The screws 9' are alike and are rotated in unison by the pinions 7c and Z on turning the spindle m by means of a milled head 0 thereon. Thereby the jaws n are caused equally to approach or recede from the intermediate clamping plane, whilst remaining parallel to their previous position.

The jaws n protrude from the frame 2', and the opposed faces of their protruding ends are provided with clamping faces go. These clamping faces p are detachable to permit substitution of clamping faces of different profile to suit the particular racket frame which is to be strung.

q is an abutment for the outer periphery of the racket frame I), and is adjustable in the clamping plane between the jaws n. For this purpose the abutment q has a screw-threaded stem 1' on which screws a milled nut s journalled in the frame i. To avoid the two screws 7', the stem 1 is not directly connected to the abutment q, but is connected thereto by a bar slotted to provide a pair of cheeks t passing one on each side of the screws 9. The abutment q is secured across and bridges the ends of the cheeks t.

The checks t are also slotted at u in the clamping plane between the jaws 7, to embrace a guide pin 1) extending transversely across between cheek plates 12 of the frame i of the clamp.

Washers w of friction-engendering material are provided on the stem 9 of each clamp c to enable the clamps c to be engaged with the brackets e with a minimum application of pressure by the winged nuts h.

a: are bars loosely pivoted on hand-adjustable screws m on each side of the machine head a and are adapted to be turned up into the position shown in Fig. 1 to provide additional lateral abutments for the racket frame I).

The handle of the racket frame 72 is held in a clamp y the jaws of which are moved equally in opposite directions by a right and left handed screw y 2 (Figs. 1 and 2) is a pin upstanding on the head of the machine and serving to locate the racket frame I) thereon.

I claim:

1. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head, a racket frame clamp frame, means for adjustably securing said clamp frame on said head, means in said clamp frame for adjustably engaging the two faces of said racket frame, an abutment in said clamp frame, and means in said clamp frame for adjusting said abutment against the outer periphery of said racket frame.

2. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head, a racket frame clamp frame, means for adjustably securing said clamp frame on said head, opposedjaws in said clamp frame, means in said clamp frame for causing said jaws mutually to approach with a'parall'el motion and engage opposite faces of said racket frame, an abutment in said clamp frame between said jaws, and means in said clamp frame for adjusting said abutment against the outer periphcry of said racket frame.

3. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head formed with a plurality of slots, a plurality of racket frame clamp frames, means on each said clamp frame for 'adjustably securing said clamp frame on said head in one of said slots, means in each said clamp frame 'for adjustably engaging the two faces of said racket frame, an abutment in each said clamp frame, and means in each said clamp frame for adjusting said abutment against the outer periphery of said racket frame.

4. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head formed with a plurality of slots, a plurality of racket frame clamp frames, means on each said clamp frame for adjustably securing said clamp frame onsaid head in one of said slots, opposed jaws in each said clamp frame, means in each said clamp frame for causing said jaws mutually to approach with a parallel motion and engage opposite faces of said racket frame, an abutment in each said clamp frame between said jaws, and means in each said clamp frame for adjusting said abutment against the outer periphery of said racket frame.

5. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head formed with groups of closely adjacent slots around its periphery, a plurality of racket frame clamps, and means on each said racket frame clamp for adjustably securing said racket frame clamp on said head in one of said slots.

6. In a machine for facilitating the stringing of rackets, a racket frame supporting head formed with a plurality of slots, a racket frame clamp frame, a screw-threaded stem depending from said clamp frame and extending through one of said slots of said head, a nut on said sorewthreaded stem, means in said clamp frame for adjustably engaging the two faces of said racket frame, an abutment in said clamp frame, and

threaded portion of both said screws, means for rotating said screws in unison, an abutment in said clamp frame between said jaws, and means in said clamp frame for adjusting said abutment against the outer periphery of said racket frame.

8. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head, a racket frame clamp frame, means for adjustablysecuring said clamp frame on said head, "means in said clamp frame for adjustably engaging the two faces of said racket frame, an

abutment in said clamp frame directed towards the outer periphery of said racket frame, a screw-threaded stem fast with said abutment, and'a nut'on said screw-threaded stem and journalled in said clamp frame.

9. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head, a racket frameclamp frame, means for adjustably securing said clamp frame on said head, a pair of screws each having right and left handed screw-threaded portions and journalled in said clamp frame, a jaw mounted on the one screw-threaded portion of both saidscrews, a jaw mounted on the other screw-threaded portion of both said screws, means for rotating said screws in unison, an abutment in said clamp frame directed towards the outer periphery of said racket frame, cheeks fast with said abutment and extending on each side of said screws, a screwthreaded stem fast with said cheeks, and a nut on said screw-threaded stem and journalled in said racket clamp frame.

10. In a machine for facilitating the stringing of lawn tennis and like rackets, a racket frame supporting head formed with a plurality of slots, a racket frame clamp frame, a screw-threaded stem depending from said clamp frame and eX- tending through one of said slots of said head, a nut on said screw-threaded stem, a of screws each having right and left handed screw-thread ed portions and journalled in said clamp frame, a jaw mounted on the one screw-threaded portion of both said screws, a jaw mounted on the other screw-threaded portion of both said screws, means for rotating said screws in unison, an abutment in said clamp frame directed towards the outer periphery of said racket frame, cheeks fast with said abutment and extending on each side of said screws, a screw-threaded stem fast with said cheeks, and a nut on said second-mentioned screw-threaded stem and journalled in said clamp frame.

WILLIAM EDWARD BERTHOLD J AFFE'I. 

